PLLA IM
Grade
IM = impact-modified / toughened PLLA
Core-shell or bio-elastomer toughened compound for drop-resistant housings and durable goods, at the cost of stiffness and clarity.
Values for the IM condition
Other PLLA grades and fills
PLLA is listed in 8 conditions; see the grade overview at PLLA.
Compare all 8 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Foamed / expanded PLLA | Physically blown biobased foam for protective packaging and insulation where low density matters more than strength. | — | 0.6 | 8 | — |
IMThis page Impact-modified / toughened PLLA | Core-shell or bio-elastomer toughened compound for drop-resistant housings and durable goods, at the cost of stiffness and clarity. | 42 | 45 | 120 | 72 Shore D |
Flame-retardant PLLA | Phosphorus/nitrogen FR compound for electronics housings and appliance parts that must meet UL 94 V-0. | 44 | 45 | 2.5 | 82 Shore D |
20% talc / mineral-filled PLLA | Cost-down, faster-crystallizing compound for rigid packaging and thermoformed trays with improved heat resistance. | 47 | 48 | 2.5 | 85 Shore D |
Nucleated fast-crystallizing PLLA | Pick for injection moulding with short cycles when a crystalline, heat-resistant part is needed straight out of the tool. | 58 | 60 | 3 | 84 Shore D |
Annealed / crystallized PLLA | Choose when the part must survive hot-fill, dishwasher or ~90–110 °C air service: crystallinity is developed by hot mold or post-mold annealing. | — | 68 | 3 | — |
Stereocomplex PLLA/PDLA blend | Blend with PDLA to form the stereocomplex crystal — melting point jumps to ~220–230 °C for the highest heat resistance available from PLA chemistry. | 68 | 70 | 5 | 85 Shore D |
30% glass-fiber reinforced PLLA | For structural biobased parts needing high stiffness and dimensional stability; must be moulded hot/annealed to exploit the heat resistance. | — | 100 | 2 | — |
What is PLLA IM?
PLLA IM is PLLA in the IM grade — core-shell or bio-elastomer toughened compound for drop-resistant housings and durable goods, at the cost of stiffness and clarity. PLLA IM has a yield strength of 42 MPa (6.09 ksi) and a tensile strength of 45 MPa (6.53 ksi) — weaker than 62% of polymer grades. Elongation at break is 120% and the elastic modulus is 2.5 GPa (0.363 Msi). PLLA IM has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 61°C (142 °F).
Advantages
- Low embodied carbon — 1.3 kg CO₂/kg, better than 100% of polymer grades
- Tough — resists crack growth — 4.5 MPa·√m (4.1 ksi·√in), better than 96% of polymer grades
- Readily welded — 75/100, better than 82% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- Limited service temperature — 50°C (122 °F), worse than 94% of polymer grades
- Needs corrosion protection — 55/100, worse than 94% of polymer grades
- Poor heat conductor — 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades
PLLA IM properties
Typical room-temperature values for PLLA IM; 27 are specific to this condition. Other listed values are PLLA reference data and may not represent this condition. Bars are the position among polymer grades.
Physical7
PLLA IM has a density of 1.24 g/cm³ (0.0448 lb/in³), heavier than 63% of polymer grades. Its glass-transition temperature is 61°C (142 °F).
Mechanical15
PLLA IM has a yield strength of 42 MPa (6.09 ksi) and a tensile strength of 45 MPa (6.53 ksi) — weaker than 62% of polymer grades. Elongation at break is 120% and the elastic modulus is 2.5 GPa (0.363 Msi).
Thermal11
PLLA IM is rated for continuous service to 50°C (122 °F). It conducts heat at 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades. Thermal expansion is 75 µm/m·K (41.7 µin/in·°F).
Electrical6
PLLA IM is an electrical insulator with a dielectric strength of 18 kV/mm (457.2 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 94% of polymer grades. UV resistance is fair.
Sustainability3
Producing a kilogram of PLLA IM takes about 50 MJ of energy and emits 1.3 kg of CO₂ — less than 99% of polymer grades. Typical recycled content is 0%.
Manufacturability8
PLLA IM's machinability is good (65/100, better than 66% of polymer grades); weldability very good (75/100); formability good (60/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with PLLA IM
Is PLLA easy to machine?
Machines like acrylic with sharp, high-rake tools and air blast — keep speeds moderate and avoid coolant soak, since frictional heat above 60 °C softens the part and hot water accelerates hydrolysis.
Can PLLA be welded?
Ultrasonic, hot-plate, vibration and laser welding all work well; solvent bonding with chloroform/dichloromethane or cyanoacrylate gives strong joints on non-crystalline surfaces.
Can PLLA be formed, bent or molded?
Dry to <250 ppm (4 h at 80 °C, or 45 °C for high-IV medical resin) before processing to prevent hydrolytic molecular-weight loss; mould at 190–220 °C melt with a cold tool (20–30 °C) for clear amorphous parts or 100–110 °C plus nucleant for crystallized heat-resistant parts; thermoforming window is narrow just above Tg.
What surface finishes work on PLLA?
Takes printing, hot stamping and vacuum metallizing after corona/plasma treatment; can be vapour-smoothed or solvent-polished, but avoid alkaline cleaners and steam sterilization (use EO or e-beam/gamma with dose control).
PLLA chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| D-isomer (D-lactide) content<1–2 % for high-crystallinity / medical PLLA; higher D lowers Tm and crystallinity | 0 – 4 | 1 |
| residual lactide monomertypically <0.1 % in medical grades | 0 – 0.5 | 0.1 |
| Sn (tin octoate catalyst residue)limited to low ppm in implant grades | 0 – 0.02 | 0.01 |
| L-lactic acid repeat unit (poly L-lactidring-opening polymerisation of L-lactide from fermented plant sugar | ≥ 96 (balance) | — |
PLLA IM — frequently asked
What is PLLA IM used for?
PLLA IM is typically used for surgical sutures, bone fixation screws/pins, biodegradable textile fiber, rigid food packaging and high-heat 3D printing filament. In short: highest-heat PLA grade; medical resorbable standard; brittle, hydrolysis sensitive.
What is the yield strength of PLLA IM?
PLLA IM has a typical yield strength of 42 MPa (6.09 ksi) and a tensile strength of 45 MPa (6.53 ksi) — weaker than 62% of polymer grades. Strength varies by condition: see the 8 listed tempers.
Is PLLA IM easy to machine?
Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Machines like acrylic with sharp, high-rake tools and air blast — keep speeds moderate and avoid coolant soak, since frictional heat above 60 °C softens the part and hot water accelerates hydrolysis.
Can PLLA IM be welded?
Yes — weldability is rated very good (75/100). Ultrasonic, hot-plate, vibration and laser welding all work well; solvent bonding with chloroform/dichloromethane or cyanoacrylate gives strong joints on non-crystalline surfaces.
What surface finishes work on PLLA IM?
Takes printing, hot stamping and vacuum metallizing after corona/plasma treatment; can be vapour-smoothed or solvent-polished, but avoid alkaline cleaners and steam sterilization (use EO or e-beam/gamma with dose control).
Can PLLA IM be formed, bent or molded?
Dry to <250 ppm (4 h at 80 °C, or 45 °C for high-IV medical resin) before processing to prevent hydrolytic molecular-weight loss; mould at 190–220 °C melt with a cold tool (20–30 °C) for clear amorphous parts or 100–110 °C plus nucleant for crystallized heat-resistant parts; thermoforming window is narrow just above Tg.
What is the maximum service temperature of PLLA IM?
PLLA IM is rated for continuous use to about 50°C (122 °F), and briefly to 80°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Luminy L-series high heat PLA resin data sheets — TotalEnergies Corbion (2023)
- Purasorb PL / PLLA bioresorbable polymer data sheets — Corbion (2022)
- RESOMER L series (poly L-lactide) product information — Evonik (2022)
- Ingeo Biopolymer technical data sheets and processing guides — NatureWorks (2023)
- ISO 527-2 / ISO 178 / ISO 75 / ISO 306 plastics test methods — ISO (2019)
- ASTM F1925 Standard Specification for Semi-Crystalline Poly(lactide) Polymer and Copolymer Resins for Surgical Implants — ASTM (2022)
- Poly(lactic acid): Synthesis, Structures, Properties, Processing and Applications — Wiley (2010)
- CAMPUS / typical PLA compound datasheets — CWFG (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.